Selective deposition of etch-stop layer for enhanced patterning

ABSTRACT

Methods, systems, and computer programs are presented for selective deposition of etch-stop layers for enhanced patterning during semiconductor manufacturing. One method includes an operation for adding a photo-resist material (M 2 ) on top of a base material (M 1 ) of a substrate, M 2  defining a pattern for etching M 1  in areas where M 2  is not present above M 1 . The method further includes operations for conformally capping the substrate with an oxide material (M 3 ) after adding M 2 , and for gap filling the substrate with filling material M 4  after the conformally capping. Further, a stop-etch material (M 5 ) is selectively grown on exposed surfaces of M 3  and not on surfaces of M 4  after the gap filling. Additionally, the method includes operations for removing M 4  from the substrate after selectively growing M 5 , and for etching the substrate after removing M 4  to transfer the pattern into M 1 . M 5  adds etching protection to enable deeper etching into M 1.

CLAIM OF PRIORITY

This application is a Continuation Application under 35 USC § 120 ofU.S. patent application Ser. No. 16/744,022, entitled “SelectiveDeposition of Etch-Stop Layer for Enhanced Patterning,” filed on Jan.15, 2020, which is a Continuation Application under 35 USC § 120 of U.S.Pat. No. 10,566,194, entitled “Selective Deposition of Etch-Stop Layerfor Enhanced Patterning,” filed on May 7, 2018, all of which areincorporated herein by reference in their entirety.

TECHNICAL FIELD

The subject matter disclosed herein generally relates to methods,systems, and programs for semiconductor etching in a semiconductormanufacturing apparatus. In some examples, deposition control andsemiconductor etching is provided during operation of the semiconductormanufacturing apparatus.

BACKGROUND

Semiconductor manufacturing has seen a reduction in critical dimension(CD) and an exponential increase in the cost of multiple patterning. Thesemiconductor manufacturing industry is transitioning to extremeultraviolet lithography (EUV) patterning to enable smaller CD featuresobtained with fewer processing steps. In many cases, the EUV photoresist (PR) material is patterned onto a silicon-based material with anaspect ratio of about 2:1.

During the EUV process, an undesired effect may occur whennon-uniformities lead to aspect ratio variation across the wafer.Another problem may arise during semiconductor manufacturing with EUVwhen the pattern transfer to the under layers is limited to the abilityof the EUV PRs to withstand the etch processes defining the pattern. Asa result, the EUV PR is quickly consumed and cannot be effectively usedto define deep patterns within the under layer.

Another problem is that very thick EUV PRs are required to successfullytransfer the pattern successfully to the under layer, but this may leadto line bending (e.g., collapse of the EUV PR lines) or poor selectivity(loss of CD) as the EUV may not penetrate all the way to the bottom ofthe line.

The background description provided herein is for the purposes ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description that may nototherwise qualify as prior art at the time of tiling, are neitherexpressly nor impliedly admitted as prior art against the presentdisclosure.

SUMMARY

Example methods, systems, and computer programs are directed toselective deposition of etch-stop layers for enhanced patterning duringsemiconductor manufacturing. In some implementations, the semiconductormanufacturing process includes extreme ultraviolet lithography (EUV)photo resist (PR) material, but the same principles may be utilized withother patterning techniques. Examples merely typify possible variations.

In some implementations, an etch stop layer, in the form of metal oxides(e.g., zirconium oxide ZrO_(x), aluminum oxide AlO_(x), hafnium oxideWOO is deposited on a EUV PR pattern to protect the pattern during etchsteps. Further, other examples of hardmasks that can be depositedselectively on SiO₂, with regard to a CH_(x) surface of carbon-basedgapfill material, include aluminum nitrides AlN, aluminum oxynitrideAlON, yttrium oxide Y2O3, yttrium nitride YN_(x), and yttriumoxynitrides YOxNy. The etch stop layer enables the transferring of thepattern much deeper into the under layer without sacrificing thecritical dimension (CD) or causing additional concerns with line bendingseen, for example, when using slender PR lines.

In one implementation, a method is provided. The method includes anoperation for adding a photo-resist material (M2) on top of a basematerial (M1) of a substrate, with M2 defining a pattern for etching M1in areas where M2 is not present above M1. The method further includesoperations for conformally capping the substrate with an oxide material(M3) after adding M2, and for gap filling the substrate with fillingmaterial M4 after the conformal capping operation. Further, a stop-etchmaterial (M5) is selectively grown on exposed surfaces of M3 and not onsurfaces of M4 after the gap filling. Additionally, the method includesoperations for removing M4 from the substrate after selectively growingM5, and for etching the substrate after removing M4 to transfer thepattern into M1. M5 adds etching protection to enable deeper etchinginto M1.

In one example, etching the substrate after removing M4 furthercomprises etching exposed surfaces of M3 in the substrate, andcontinuing etching the substrate to transfer the pattern into M1.

In one example, M2 is a carbon-based material.

In one example, M3 is one of silicon dioxide or aluminum oxide.

In one example, M4 is a carbon-based material sacrificial material.

In one example, M5 is a metal oxide.

In one example, conformally capping the substrate with M3 furthercomprises performing a low-damage plasma enhanced atomic layerdeposition.

In one example, gap filling the substrate with filling material M4further comprises alternating depositing M4 and etching M4 to fill gapsin the substrate.

In one example, selectively growing M5 further comprises utilizing anatomic-layer-deposition process to deposit M5.

In one example, removing M4 from the substrate further comprisesperforming plasma ashing to remove M4.

In another implementation, a semiconductor manufacturing apparatuscomprises a processing chamber and a controller for controllingprocessing of a substrate within the processing chamber. The controllercauses the processing chamber to perform operations comprising: adding aphoto-resist material (M2) on top of a base material (M1) of asubstrate, with M2 defining a pattern for etching M1 in areas where M2is not present above M1; conformally capping the substrate with an oxidematerial (M3) after adding M2; gap filling the substrate with fillingmaterial M4 after the conformal capping operation; selectively growingstop-etch material (M5) on exposed surfaces of M3 and not on surfaces ofM4 after the gap filling: removing M4 from the substrate afterselectively growing M5; and etching the substrate after removing M4 totransfer the pattern into M1, wherein M5 adds etching protection toenable deeper etching into M1 than when utilizing M2 without M5.

In one example, etching the substrate after removing M4 furthercomprises etching exposed surfaces of M3 in the substrate, andcontinuing etching the substrate to transfer the pattern into M1.

In one example, M2 is a carbon-based material.

In one example, M3 is one of silicon dioxide or aluminum oxide.

In one example, M4 is carbon.

In one example, M5 is a metal oxide.

In one example, conformally capping the substrate with M3 furthercomprises performing a low-damage plasma enhanced atomic layerdeposition.

In one example, gap filling the substrate with filling material M4further comprises alternating depositing M4 and etching M4 to fill gapsin the substrate.

In one example, selectively growing M5 further comprises utilizing anatomic-layer-deposition process to deposit M5.

In one example, removing M4 from the substrate further comprisesperforming plasma oiling to remove M4.

BRIEF DESCRIPTION OF THE DRAWINGS

Various ones of the appended drawings merely illustrate exampleembodiments of the present disclosure and cannot be considered aslimiting its scope.

FIG. 1 is an etching chamber, according to some example embodiments.

FIGS. 2-10 illustrate a sequence of operations for etching a substratein a semiconductor processing apparatus, according to some exampleembodiments.

FIG. 11 is a flowchart of a method for processing a substrate in asemiconductor processing apparatus, according to some exampleembodiments.

FIGS. 12-14 illustrate a second sequence of operations for etching thesubstrate in a semiconductor processing apparatus, according to someexample embodiments.

FIG. 15 is a flowchart of a second method for processing a substrate ina semiconductor processing apparatus, according to some exampleembodiments.

FIGS. 16-20 illustrate a third sequence for etching a substrate in asemiconductor processing apparatus, according to some exampleembodiments.

FIG. 21 is a flowchart of a third method for processing a substrate in asemiconductor processing apparatus, according to some exampleembodiments.

FIG. 22 is a block diagram illustrating an example of a machine uponwhich one or more example embodiments may be implemented, or by whichone or more example embodiments may be controlled.

DETAILED DESCRIPTION

In some examples, selective deposition of etch-stop layers for enhancedpatterning during semiconductor manufacturing is presented. Unlessexplicitly stated otherwise, components and functions are optional andmay be combined or subdivided, and operations may vary in sequence or becombined or subdivided. In the following description, for purposes ofexplanation, numerous specific details are set forth to provide athorough understanding of example embodiments. It will be evident to oneskilled in the art, however, that the present subject mailer may bepracticed without these specific details.

The presented embodiments can provide several benefits. First, there isthe ability to extend the pattern deeper into the under layer when usingthe etch-stop layer, while using the same EUV PR thickness as inprevious implementations. This means that no additional changes areneeded for existing EUV processes. Second, a combination of processsteps (including adding conformal silicon oxide (SiO_(x)) and gapfilling the uneven surfaces on the substrate surface) are used to enableselective growth of the etch-stop layer onto the EUV PR.

Third, there is no (or very minimal) line bending or CD loss whenextending the pattern deeper into the under layer. Fourth, the presentedimplementations may be applied to any structure substrates that needselective growth of etch-stop layers on etched lines as compared to theopen space areas for enhanced patterning. These are just some of thebenefits that may be obtained using the described methods. Otherbenefits are possible.

FIG. 1 shows an etching chamber 100, according to one embodiment.Exciting an electric field between two electrodes is one of the methodsto obtain radiofrequency (RF) gas discharge in an etching chamber. Whenan oscillating voltage is applied between the electrodes, the dischargeobtained is referred to as a Capacitive Coupled Plasma (CCP) discharge.

Plasma 102 may be created utilizing stable feedstock gases to obtain awide variety of chemically reactive by-products created by thedissociation of the various molecules caused by electron-neutralcollisions. The chemical aspect of etching involves the reaction of theneutral gas molecules and their dissociated by-products with themolecules of the to-be-etched surface, and producing volatile molecules,which can be pumped away. When plasma is created, the positive ions areaccelerated from the plasma across a space-charge sheath separating theplasma from chamber walls to strike the wafer surface with enough energyto remove material from the wafer surface. This is known as ionbombardment or ion sputtering. Some industrial plasmas, however, do notproduce ions with enough energy to efficiently etch a surface by purelyphysical means.

A controller 116 manages the operation of the chamber 100 by controllingthe different elements in the chamber, such as RF generator 118, gassources 122, and gas pump 120. In one embodiment, fluorocarbon gases,such as CF₄ and C—C₄F_(8,) are used in a dielectric etch process fortheir anisotropic and selective etching capabilities, but the principlesdescribed herein can be applied to other plasma-creating gases. Thefluorocarbon gases are readily dissociated into chemically reactiveby-products that include smaller molecular and atomic radicals. Thesechemically reactive by-products etch away the dielectric material, whichin one embodiment can be SiO₂ or SiOCH for low-k devices.

The chamber 100 illustrates a processing chamber with a top electrode104 and a bottom electrode 108. The top electrode 104 may be grounded orcoupled to an RF generator (not shown), and the bottom electrode 108 iscoupled to RF generator 118 via matching network 114. RF generator 118provides RF power in one, two, or three different RF frequencies.According to the desired configuration of the chamber 100 for aparticular operation, at least one of the three RF frequencies may beturned on or off. In the embodiment shown in FIG. 1 , RF generator 118provides 2 MHz, 27 MHz, and 60 MHz frequencies, but other frequenciesare also possible.

The chamber 100 includes a gas showerhead on the top electrode 104 toinput gas into the chamber 100 provided by gas source(s) 122, and aperforated confinement ring 112 that allows the gas to be pumped out ofthe chamber 100 by gas pump 120. In some example embodiments, the gaspump 120 is a turbomolecular pump, but other type of gas pumps may beutilized.

When substrate 106 is present in the chamber 100, silicon focus ring 110is situated next to the substrate 106 such that there is a uniform RFfield at the bottom surface of the plasma 102 for uniform etching on thesurface of the substrate 106. The embodiment of FIG. 1 shows a triodereactor configuration where the top electrode 104 is surrounded by asymmetric RF ground electrode 124. Insulator 126 is a dielectric thatisolates ground electrode 124 from top electrode 104.

Each frequency may be selected for a specific purpose in the wafermanufacturing process. In the example of FIG. 1 , with RF powersprovided at 2 MHz, 27 MHz, and 60 MHz, the 2 MHz RF power provides ionenergy control, and the 27 MHz and 60 MHz power provide control of theplasma density and the dissociation patterns of the chemistry. Thisconfiguration, where each RF power may be turned on or off, enablescertain processes that use ultra-low ion energy on the substrates orwafers, and certain processes (e.g., soft etch for low-k materials)where the ion energy has to be low (under 100 or 200 eV).

In another embodiment, a 60 MHz RF power is used on the top electrode104 to get ultra-low energies and very high density. This configurationallows chamber cleaning with high density plasma when the substrate isnot in the chamber 100, while minimizing sputtering on the electrostatic chuck (ESC) surface. The ESC surface is exposed when thesubstrate is not present, and any ion energy on the surface should beavoided, which is why the bottom 2 MHz and 27 MHz power supplies may beoff during cleaning.

FIG. 2-10 illustrate a sequence of operations for etching a substrate ina semiconductor processing apparatus, according to some exampleembodiments. This sequence of operations illustrates how to add anetch-stop layer to provide additional protection from etchingoperations, allowing transfer of the pattern lower down into theunderlying layers, further than by using EUV PR alone.

FIG. 2 illustrates operation 202, Where a PR material (M2 206), ispatterned onto a base material (M1 204) resulting in structure 200. Insome example embodiments, the M1 204 material is a silicon oxide or asilicon nitride (Si_(x)N_(y)) type of material, but other materials maybe used. In some embodiments, the aspect ratio for M1 204 is about 2:1,plus or minus 10%, but other aspect ratios may be used. The aspect ratiodefines the relationship between the different dimensions (in this case,height of a feature against the width of the feature).

M2 206 may be a carbon-based material with some embedded dopers. EUV,also referred to as EUVL, is a lithography technology that employs anextreme ultraviolet wavelength (e.g., 13.5 nm). In some implementations,the EUV tool is a laser-driven tin (Sn) plasma light source, wherereflective optics comprise multilayer mirrors, contained within ahydrogen gas ambient.

The resulting structure 200 has some dense areas (e.g., left side aboveM1 204) and some isolated areas (e.g., center area above M1 204). Thegoal of the etching process is to transfer a pattern onto M1 204 byetching down the areas of M1 204 not covered by M2 206. In some cases,EUV is used in the process, but EUV PRs are susceptible to damagebecause they tend to lack stability for withstanding strong etches.

With the structure 200, to pattern M1 204 with PR M2 206, it is possibleto etch into M1 204, but not very deeply. Some applications requiredeeper etches that may etch into more than one layer, and PR M2 206 isnot adequate for this applications as M2 206 may wear off and stopprotecting M1 204.

The operations described below with reference to FIGS. 3-10 show how toadd protection to M2 206 to allow for deeper etching into M1 204. Thisprotection includes adding a stop-etch layer above M2 206 to allowdeeper etching without completely wearing off M2 206. The stop-etchlayer is a layer of material placed above the PR M2 206 that protects M2206 during etching. Although the term “stop” is used, a person skilledin the art would appreciate that the stop-etch layer may not completelyavoid some of the etching on M2 206, but the stop-etch layer providesenough protection to M2 206 to avoid completely wearing off M2 206during deep etching. That is, the stop-etch layer provides, at least,enough protection for M2 206 to avoid etching M1 204 material under PRM2 206.

One approach might be simply to add the stop-etch layer above M2 206,but that would also mean placing the stop-etch layer above uncoveredareas of M1 204, which would not be effective. The goal is to place thestop-etch layer above M2 206 without adding the stop-etch layer directlyon top of M1 204.

FIG. 3 illustrates operation 302 where a material M3 304 is deposited toconformally cap structure 200 with material M3 304, resulting instructure 300. When structure 200 is conformally capped with M3 304, theangles and proportions are preserved; that is, M3 forms a uniform layerabove both M1 204 and M2 206.

The purpose of M3 304 is to provide a surface for the etch-stop layer togrow onto. In some example embodiments, M3 304 is an oxide, such as anatomic layer deposition (ALD) oxide. In some example embodiments, M3 304is silicon dioxide SiO₂ or aluminum oxide Al₂O₃, but other materials mayalso be used.

In some example embodiments, operation 302, for placing M3 304, isperformed with a low-damage plasma enhanced atomic layer deposition(PEALD). ALD is a vapor phase thin film deposition technique, which istypically carried out in a heated reactor maintained at asub-atmospheric pressure. Substrates to be coated with an ALD film areplaced in the reactor and allowed to equilibrate with the reactortemperature before the ALD process is started.

PEALD is an energy-enhanced ALD method where the surface of thesubstrate is exposed to the species generated by a plasma during thereactant step. Typical plasmas used during PEALD are those generated inO₂, N₂, and H₂ reactant gases or combinations thereof. Such plasmas canreplace ligand-exchange reactions typical of water H₂O or ammonia NH₃,and they can be employed to deposit metal oxides, metal nitrides, andmetal films.

FIG. 4 illustrates operation 402 where open areas are filled withmaterial M4 404, resulting in structure 400. In some exampleembodiments, M4 404, also referred to herein as filling material, isamorphous carbon, but other materials are also possible. After adding M4404, the top of the features of M3 304 are exposed, while the othersurfaces of the features are covered by M4 404.

M4 404 acts as a sacrificial material, as discussed in more detailbelow, to allow the stop-etch layer to grow on the top surfaces of M3304 but not on other surfaces. In some example embodiments, operation402 is performed in an etching environment, where hydrogen is added inthe process, and along with depositing, the process also etches thematerial (e.g., both etching and depositing are being performed). Thisway, it is possible to gap till the open areas. In the tight spaces,etching is only performed at the top but not at the bottom, so it ispossible to gap fill.

The reason that M4 404 is used is that this carbon-based filler allowsto selectively grow the stop-etch layer on the areas where M4 404 is notpresent. That is, the stop-etch layer grows on areas without M4 404exposed and will not grow on areas where M4 404 is exposed. This way, itis possible to expose M3 304 to the stop-etch layer.

FIG. 5 illustrates operation 502 where the stop-etch layer (material M5504) is grown above exposed M3 304, resulting in structure 500. In someexample embodiments, operation 502 is an ALD process to deposit M5 504selectively on M3 304. In some example embodiments, the ALD includesalternating a first precursor with a second precursor, for a layeredgrowth approach.

In some example embodiments, M5 504 is a metal oxide (MO_(x)) (e.g.,zirconium oxide ZrO_(x), aluminum oxide AlO_(x), hafnium oxide HfO_(x))that will not grow on M4 404 because of the carbon presence (e.g., M4404 may be CH_(x) terminated). For example, M5 504 may be aluminumoxide. However, M5 504 will grow on M3 304, which may be a SiO_(x)surface OH terminated.

FIG. 6 illustrates operation 602 where M4 404 is removed, resulting instructure 600. As described above, the purpose of gap filling with M4404 is to allow the selected growth of M5 504. After the stop-etch layerM5 504 has been added, M4 404 may be removed.

In some example embodiments, M4 404 may be removed by ashing, which is astraightforward operation because carbon is easy to remove. For example,a hydrogen plasma may be utilized to remove M4 404.

Plasma ashing is a process for removing material from a substrate. Usinga plasma source, a single-atom substance, known as a reactive species,is generated. Oxygen or fluorine are common reactive species. Thereactive species combine with the material to be removed to form ash,which is removed with a vacuum pump.

FIG. 7 illustrates operation 702 where M3 304 is removed on the exposedsurfaces, resulting in structure 700. After M4 404 has been removed, theetching process may continue to transfer the pattern defined by M2 206into M1 204. In some example embodiments, operation 602 is performed viaetching to remove M3 304.

At this point, part of the top surface of M1 204 is uncovered, while thepattern defined by M2 206 has extra protection against etching becauseM2 206 is covered with M5 504. Deep etching of M1 204 may now beperformed, as described below.

FIG. 8 illustrates operation 802 for etching unexposed surfaces of M1204, resulting in structure 800. Etching is performed to transfer thepattern into M1204. As M1 204 is being etched, M5 504 is also beingremoved, until M5 504 is completely removed, but the etching maycontinue because M2 206 is still present.

Structure 800 shows the gradual etching into M1 204 and the wearing offof M5 504. Because M5 504 is present, it is possible to go deeper intoM1 204.

FIG. 9 illustrates operation 902 where etching continues into M1 204while etching away M3 304, resulting in structure 900. At the end ofoperation 902, M3 304 has been etched away (not shown), or at least mostof it, but M2 206 still continues providing protection to M1 204 totransfer the pattern and go deeper into M1 204.

FIG. 10 illustrates operation 1002 where M5 504 and M3 304 have beenremoved and some of M2 206 has also been etched away, resulting instructure 1000. At the end of operation 1002, the desired sections of M1204 have been etched away, while some of M2 206 still remains, resultingin the desired CD being maintained.

As illustrated in structure 1000, some of the edges of M2 206 have beenrounded off due to etching. A person skilled in the art would readilyappreciate that FIGS. 2-10 show an ideal representation of thematerials, including perfect straight lines. However, during thedifferent operations, depositions and etching may result in slightvariations in the materials (e.g., thickness and uneven corners).

In summary, by gap filling with M4 404, it is possible to selectivelygrow M5 504 above M2 206. M3 304 allows M5 504 to grow on a consistentsurface.

FIG. 11 is a flowchart of a method 1100 for processing a substrate in asemiconductor processing apparatus, according to some exampleembodiments. While the various operations in this flowchart arepresented and described sequentially, one of ordinary skill willappreciate that some or all of the operations may be executed in adifferent order, be combined or omitted, or be executed in parallel.FIG. 11 summarizes the process illustrated in FIGS. 2-10 .

At operation 202, a pattern M2 206 is created above material M1 204, Insome example embodiments, EUV is utilized to create the pattern, butother lithography methods may also be utilized.

From operation 202, the method flows to operation 302 where M2 206 isconformally capped with M3 304. At operation 402, gaps are filled withmaterial M4 404, while preserving the top surfaces of M3 304 that areabove the pattern defined by M2 206.

From operation 402, the method flows to operation 502. Once M4 404 hasbeen added, it is possible to selectively grow M5 504 on top of M3 304but not on top of M4 404.

From operation 502, the method flows to operation 602. Once M4 404 hasserved its purpose, enabling to selectively grow M5 504, M4 404 isremoved.

From operation 602, the method flows to operation 702, where M3 304sections that are not protected by M5 504 are etched away.

From operation 702, the method flows to operation 802, where etching ofthe base layer of M1 202 begins. As M1 202 is being etched away, the topsurface of M5 504 is also being etched away, but still providesprotection to the pattern defined by M2 206.

From operation 802, the method flows to operation 902, where etching onM1 continues while also etching away M3 304.

From operation 902, the method flows to operation 1002. After M3 304 hasbeen etched away, the etching on M1 204 continues, which means that thepattern of M2 206 is also gradually being etched away. However, M2 206is not completely etched away, thereby guaranteeing that the pattern istransferred into M1 204.

FIGS. 12-14 illustrate a second sequence of operations for etching thesubstrate in a semiconductor processing apparatus, according to someexample embodiments. The second sequence also enables the use of EUV PRto transfer the pattern lower into the under layers, which would havenot been possible with the EUV PR alone.

The second sequence also includes operations 202, 302, and 402, asillustrated above with reference to FIGS. 2-4 . However, from operation402, the second sequence flows from operation 402 to operation 1202 ofFIG. 12 .

FIG. 12 illustrates operation 1202 where M4 404 is converted to materialM4-2 1204, resulting in structure 1200. In some example embodiments, M4402 is a CHx surface that is converted to a CFx surface M4-2 1204. TheCFx surface may offer more non-wetting surface for the desiredchemistries than the CHx surface, thereby improving the selectivity ofdepositing M5 504. In some example embodiments, M4 402 is converted toM4-2 1204 by fluorinating M4 402.

The fluorination of the carbon film (CHx) may be performed by acapacitively coupled plasma or a remote plasma assisted process thatenable fluorinating the carbon surface.

FIG. 13 illustrates operation 1302 where the stop-etch layer (materialM5 504) is grown above exposed M3 304, resulting in structure 1300. Asin operation 502, the ALD process is utilized to deposit M5 504selectively on M3 304, The metal oxide (MO_(x)) will not grow onto theCFx terminated surface (M4-2 1204) enabling selective growth on the SiOxsurface (M3 304).

FIG. 14 illustrates operation 1402 where M4-2 1204 is removed, resultingin structure 1400, which is similar to structure 600 of FIG. 6 . In someexample embodiments, M4-2 1204 may be removed by ashing, which is asimple operation because carbon is easy to remove. For example, ahydrogen plasma may be utilized to remove M4-2 1204.

From operation 1402, the method flows to operation 702 of FIG. 7 , andthe remainder of the operations in the second sequence are the same asthe operations following operation 702 in the first sequence.

FIG. 15 is a flowchart of a second method 1500 for processing asubstrate in a semiconductor processing apparatus, according to someexample embodiments. While the various operations in this flowchart arepresented and described sequentially, one of ordinary skill willappreciate that some or all of the operations may be executed in adifferent order, be combined or omitted, or be executed in parallel.

Operations 202, 302, and 402 are the same as described above withreference to FIG. 11 . At operation 1202, material M4 404 is converted(e.g., by fluorinating) to a different type of material M4-2 1204.

From operation 1202, the method flows to operation 1302, where materialM5 504 is selectively grown on M3 304, but not on M4-2 1204.

From operation 1302, the method flows to operation 1402, where materialM4-2 1204 is removed, such as by ashing or other type of etchingprocess.

From operation 1402, the method flows to Operation 702, and the reminderof the steps are the same as described above with reference to FIG. 11 .

FIGS. 16-20 illustrate a third sequence for etching a substrate in asemiconductor processing apparatus, according to some exampleembodiments. The third sequence is a hybrid approach, where a newmaterial M6 1604 is added on top of M3 304, before gap filling with M4404, to improve selectivity when growing M5 504.

The third sequence includes operations 202 and 302, as described above.From operation 302, the third sequence continues in operation 1602. FIG.16 illustrates operation 1602 where M3 304 is capped with a conformallayer of material M6 1604, resulting in structure 1600.

In some example embodiments, M6 1604 is a fluorocarbon CF_(x). In someexample embodiments, operation 1602, for placing M6 1604, is performedwith a low-damage plasma enhanced atomic layer deposition (PEALD).

FIG. 17 illustrates operation 1702 where open areas are filled withmaterial M4 404, resulting in structure 1700. Operation 1702 is similarto operation 402 described above with reference to FIG. 4 , except forthe presence of M6 1604 on the top surface.

FIG. 18 illustrates operation 1802 where top surfaces of M6 1604,associated with the pattern to be transferred, are removed to expose M3304 before growing M5 504. The result is structure 1800. In some exampleembodiments, the top surfaces of ME 1604 are removed with a light etchoperation to expose the oxide surface, but other removal operations arepossible,

FIG. 19 illustrates operation 1902 where the stop-etch layer (materialM5 504) is grown above exposed M3 304, resulting in structure 1900. Thepresence of ME 1604 improves selectivity when growing M5 504 because M61604 provides a separation between M3 304 and M4 404; therefore, theselectivity is improved. The metal oxide may be deposited via by MOCVD(Metal Organic CVD), and the metal oxide will not grow onto the CFx orCFx surfaces. This will enable growth of MOx selectivity on SiOxsurface, which may be —OH terminated.

FIG. 20 illustrates operation 2002 where M4 404 and M6 1604 are removed,resulting in structure 2000. As described above, the purpose of gapfilling with M4 404 is to allow the selected growth of M5 504. After thestop-etch layer M5 504 has been added, M4 404 and ME 1604 may beremoved.

In some example embodiments, M4 404 and M6 1604 may be removed byashing, which is a simple operation because carbon is easy to remove.For example, a hydrogen plasma may be utilized to remove M4 404.

After operation 2002, the third sequence continues at operation 702, asillustrated in FIG. 7 , and the remainder of the operations are the sameas in the first sequence described in FIG. 11 .

FIG. 21 is a flowchart of a third method 2100 for processing a substratein a semiconductor processing apparatus, according to some exampleembodiments. While the various operations in this flowchart arepresented and described sequentially, one of ordinary skill willappreciate that some or all of the operations max be executed in adifferent order, be combined or omitted, or be executed in parallel.

Operations 202 and 302 are the same as described above with reference toFIG. 11 . At operation 1602, a layer of material M6 1604 is conformallygrown above M3 304.

From operation 1602, the method flows to operation 1702, where openareas are gap filled with M4 404. From operation 1702, the method flowsto operation 1802, where the top surfaces of M4 404 and M6 1604 areremoved to expose M3 304.

From operation 1802, the method flows to operation 1902, where M5 504 isselectively grown on M3 304. From operation 1902, the method flows tooperation 2002, where M4 404 and M6 1604 are removed.

From operation 2002, the method flows to operation 702, as describedabove with reference to FIG. 7 , and the remainder of the operations arethe same as described above with reference to FIG. 11 .

FIG. 22 is a block diagram illustrating an example of a machine 2200upon or by which one or more example process embodiments describedherein may be implemented or controlled. In alternative embodiments, themachine 2200 may operate as a standalone device or may be connected(e.g., networked) to other machines. In a networked deployment, themachine 2200 may operate in the capacity of a server machine, a clientmachine, or both in server-client network environments. In an example,the machine 2200 may act as a peer machine in a peer-to-peer (P2P) (orother distributed) network environment. Further, while only a singlemachine 2200 is illustrated, the term “machine” shall also be taken toinclude any collection of machines that individually or jointly executea set (or multiple sets) of instructions to perform any one or more ofthe methodologies discussed herein, such as via cloud computing,software as a service (SaaS), or other computer cluster configurations.

Examples, as described herein, may include, or may operate by, logic, anumber of components, or mechanisms. Circuitry is a collection ofcircuits implemented in tangible entities that include hardware (e.g.,simple circuits, gates, logic, etc.). Circuitry membership may beflexible over time and underlying hardware variability. Circuitriesinclude members that may, alone or in combination, perform specifiedoperations when operating. In an example, hardware of the circuitry maybe immutably designed to carry out a specific operation (e.g.,hardwired). In an example, the hardware of the circuitry may includevariably connected physical components (e.g., execution units,transistors, simple circuits, etc.) including a computer-readable mediumphysically modified (e.g., magnetically, electrically, by moveableplacement of invariant massed particles, etc.) to encode instructions ofthe specific operation. In connecting the physical components, theunderlying electrical properties of a hardware constituent are changed(for example, from an insulator to a conductor or vice versa). Theinstructions enable embedded hardware (e.g., the execution units or aloading mechanism) to create members of the circuitry in hardware viathe variable connections to carry out portions of the specific operationwhen in operation. Accordingly, the computer-readable medium iscommunicatively coupled to the other components of the circuitry whenthe device is operating. In an example, any of the physical componentsmay be used in more than one member of more than one circuitry. Forexample, under operation, execution units may be used in a first circuitof a first circuitry at one point in time and reused by a second circuitin the first circuitry, or by a third circuit in a second circuitry, ata different time.

The machine (e.g., computer system) 2200 may include a hardwareprocessor 2202 (e.g., a central processing unit (CPU), a hardwareprocessor core, or any combination thereof), a graphics processing unit(GPU) 2203, a main memory 2204, and a static memory 2206, some or all ofwhich may communicate with each other via an interlink (e.g., bus) 2208.The machine 2200 may further include a display device 2210, analphanumeric input device 2212 (e.g., a keyboard), and a user interface(UI) navigation device 2214 (e.g., a mouse), In an example, the displaydevice 2210, alphanumeric input device 2212, and LII navigation device2214 may be a touch screen display. The machine 2200 may additionallyinclude a mass storage device (e.g., drive unit) 2216, a signalgeneration device 2218 (e.g., a speaker), a network interface device2220, and one or more sensors 2221, such as a Global Positioning System(GPS) sensor, compass, accelerometer, or other sensor. The machine 2200may include an output controller 2228, such as a serial (e.g., universalserial bus (USB)), parallel, or other wired or wireless (e.g., infrared(IR), near field communication (NFC), etc.) connection to communicatewith or control one or more peripheral devices a printer, card reader,etc.).

The mass storage device 2216 may include a machine-readable medium 2222on which is stored one or more sets of data structures or instructions2224 (e.g., software) embodying or utilized by any one or more of thetechniques or functions described herein. The instructions 2224 may alsoreside, completely or at least partially, within the main memory 2204,within the static memory 2206, within the hardware processor 2202, orwithin the GPU 2203 during execution thereof by the machine 2200. In anexample, one or any combination of the hardware processor 2202, the GPU2203, the main memory 2204, the static memory 2206, or the mass storagedevice 2216 may constitute machine-readable media.

While the machine-readable medium 2222 is illustrated as a singlemedium, the term “machine-readable medium” may include a single medium,or multiple media. (e.g., a centralized or distributed database, and/orassociated caches and servers) configured to store the one or moreinstructions 2224.

The term “machine-readable medium” may include any medium that iscapable of storing, encoding, or carrying instructions 2224 forexecution by the machine 2200 and that cause the machine 2200 to performany one or more of the techniques of the present disclosure, or that iscapable of storing, encoding, or carrying data structures used by orassociated with such instructions 2224. Non-limiting machine-readablemedium examples may include solid-state memories, and optical andmagnetic media. In an example, a massed machine-readable mediumcomprises a machine-readable medium 2222 with a plurality of particleshaving invariant (e.g., rest) mass. Accordingly, massed machine-readablemedia are not transitory propagating signals. Specific examples ofmassed machine-readable media may include non-volatile memory, such assemiconductor memory devices (e.g., Electrically Programmable Read-OnlyMemory (EPROM), Electrically Erasable Programmable Read-Only Memory(EEPROM)) and flash memory devices; magnetic disks, such as internalhard disks and removable disks; magneto-optical disks; and CD-ROM andDVD-ROM disks.

The instructions 2224 may further be transmitted or received over acommunications network 2226 using a transmission medium via the networkinterface device 2220.

Throughout this specification, plural instances may implementcomponents, operations, or structures described as a single instance.Although individual operations of one or more methods are illustratedand described as separate operations, one or more of the individualoperations may be performed concurrently, and nothing requires that theoperations be performed in the order illustrated. Structures andfunctionality presented as separate components in example configurationsmay be implemented as a combined structure or component. Similarly,structures and functionality presented as a single component may beimplemented as separate components. These and other variations,modifications, additions, and improvements fall within the scope of thesubject matter herein.

The embodiments illustrated herein are described in sufficient detail toenable those skilled in the art to practice the teachings disclosed,Other embodiments may be used and derived therefrom, such thatstructural and logical substitutions and changes may be made withoutdeparting from the scope of this disclosure. The Detailed Description,therefore, is not to be taken in a limiting sense, and the scope ofvarious embodiments is defined only by the appended claims, along withthe full range of equivalents to which such claims are entitled.

As used herein, the term “or” may be construed in either an inclusive orexclusive sense. Moreover, plural instances may be provided forresources, operations, or structures described herein as a singleinstance. Additionally, boundaries between various resources,operations, modules, engines, and data stores are somewhat arbitrary,and particular operations are illustrated in a context of specificillustrative configurations. Other allocations of functionality areenvisioned and may fall within a scope of various embodiments of thepresent disclosure. In general, structures and functionality presentedas separate resources in the example configurations may be implementedas a combined structure or resource. Similarly, structures andfunctionality presented as a single resource may be implemented asseparate resources. These and other variations, modifications,additions, and improvements fall within a scope of embodiments of thepresent disclosure as represented by the appended claims. Thespecification and drawings are, accordingly, to be regarded in anillustrative rather than a restrictive sense.

What is claimed is:
 1. A method comprising: adding a photo-resistmaterial (M2) on top of a base material (M1) of a substrate, M2 defininga pattern for etching M1 in areas where M2 is not present above M1;conformally capping the substrate with an oxide material (M3) afteradding M2; depositing a layer of a conformal material (M6) afterconformally capping the substrate; gap filling the substrate withfilling material M4 after depositing M6; removing top surfaces of M6from the substrate after the gap filling; selectively growing stop-etchmaterial (M5) on exposed surfaces of M3; removing M4 from the substrateafter selectively growing M5; and etching the substrate after removingM4 to transfer the pattern into M1.
 2. The method as recited in claim 1,wherein etching the substrate after removing M4 further comprises:etching exposed surfaces of M3 on the substrate; and continue etchingthe substrate to transfer the pattern into M1.
 3. The method as recitedin claim 1, wherein depositing the layer of M6 includes performing alow-damage plasma enhanced atomic layer deposition (PEALD).
 4. Themethod as recited in claim 1, wherein removing M6 from the substrateafter the gap filling includes performing a light etch operation toexpose a surface of the oxide material.
 5. The method as recited inclaim 1, wherein selectively growing M5 is performed by MOCVD (MetalOrganic CVD).
 6. The method as recited in claim 1, wherein removing M4from the substrate after selectively growing M5 includes removing byashing.
 7. The method as recited in claim 1, wherein conformally cappingthe substrate with M3 further comprises: performing a low-damage plasmaenhanced atomic layer deposition.
 8. The method as recited in claim 1,wherein M2 is a carbon-based material.
 9. The method as recited in claim1, wherein M3 is one of silicon dioxide or aluminum oxide.
 10. Themethod as recited in claim 1, wherein M4 is a CHx surface.
 11. Themethod as recited in claim 1, wherein M6 is a fluorocarbon.
 12. Themethod as recited in claim 1, wherein M5 is a metal oxide or oxynitride.13. A semiconductor manufacturing apparatus comprising: a processingchamber; and a controller for controlling processing of a substratewithin the processing chamber, wherein the controller causes theprocessing chamber to perform operations comprising: adding aphoto-resist material (M2) on top of a base material (M1) of asubstrate, M2 defining a pattern for etching M1 in areas where M2 is notpresent above M1; conformally capping the substrate with an oxidematerial (M3) after adding M2; depositing a layer of a conformalmaterial (M6) after conformally capping the substrate; gap filling thesubstrate with filling material M4 after depositing M6; removing topsurfaces of M6 from the substrate after the gap filling; selectivelygrowing stop-etch material (M5) on exposed surfaces of M3; removing M4from the substrate after selectively growing M5; and etching thesubstrate after removing M4 to transfer the pattern into M1.
 14. Thesemiconductor manufacturing apparatus as recited in claim 13, whereinetching the substrate after removing M4 further comprises: etchingexposed surfaces of M3 on the substrate; and continue etching thesubstrate to transfer the pattern into M1.
 15. The semiconductormanufacturing apparatus as recited in claim 13, wherein depositing thelayer of M6 includes performing a low-damage plasma enhanced atomiclayer deposition (PEALD).
 16. The semiconductor manufacturing apparatusas recited in claim 13, wherein removing the top surfaces of M6 from thesubstrate after the gap filling includes performing a light etchoperation to expose a surface of the oxide material.
 17. Thesemiconductor manufacturing apparatus as recited in claim 13, whereinselectively growing M5 is performed by MOCVD (Metal Organic CVD). 18.The semiconductor manufacturing apparatus as recited in claim 13,wherein removing M4 from the substrate after selectively growing M5includes removing by ashing.
 19. The semiconductor manufacturingapparatus as recited in claim 13, wherein conformally capping thesubstrate with M3 further comprises: performing a low-damage plasmaenhanced atomic layer deposition.
 20. The semiconductor manufacturingapparatus as recited in claim 13, wherein M2 is a carbon-based material,wherein M3 is one of silicon dioxide or aluminum oxide, wherein M4 is aCHx surface, wherein M5 is a metal oxide or oxynitride, wherein M6 is afluorocarbon.